Removal of grit from baby leafy salad vegetables by combinations of sanitiser and surfactant

Grit composed of dirt, sand and small stones adheres to baby leafy salad vegetables during the growing period and can sometimes be difficult to remove with sanitiser only or tap water. For the first time, the effect of a surfactant, sodium dodecyl sulphate (SDS), alone (0.025, 0.05, 0.1 % SDS) and in combination (0.05 % SDS) with peroxyacetic acid (40 mg L^-1, PAA), on grit removal, quality, shelf-life and taste of baby spinach was investigated. Increasing SDS from 0.025 to 0.1 % resulted in a 21-50 % increase in grit removal on spinach and coral lettuce. Overall, SDS treatments had no effect on microbial growth, colour and electrolyte leakage during shelf-life. An increase in bruising, sliming and yellowing scores was also observed regardless of the treatment, reaching an unacceptable score (< 3) by day-12 for all samples, however yellowing scores were still within an acceptable range (> 3) on d-14. There were no differences in sensorial attributes namely, flavour, aroma and texture, between baby spinach samples treated with PAA alone or in combination with SDS. These results demonstrate that SDS treatment can be used to increase grit removal on baby leafy salad vegetables without compromising quality.